Question

I have a weird problem. My query in C#/ASP.NET returns results 5 times. I tried brakepoint-ing but I can’t find the error. I have 2 related tables. One table loads on PAGE_LOAD and when the user click on a cell, it shows the content from another table related to that cell. It’s very simple.

    //PAGE LOAD
protected void Page_Load(object sender, EventArgs e)
{
    if (!IsPostBack)
    {
        OleDbConnection myConnection = new OleDbConnection("Provider=Microsoft.Jet.OLEDB.4.0;Data Source=" + dbpath + "/secure_user/data/data.mdb");
        OleDbDataAdapter adapter = new OleDbDataAdapter("SELECT Project,Manager,Customer,Deadline FROM projects WHERE Username='" + uname + "'", myConnection);
        DataTable table = new DataTable();
        adapter.Fill(table);
        adapter.Dispose();
        GridView1.DataSource = table;
        GridView1.DataBind();
    }
}

It loads projects table to the GridView. Now when I click a certain project, it displays more information about that project:

protected void GridView1_SelectedIndexChanged(object sender, EventArgs e)
{
    GridViewRow row = GridView1.SelectedRow;
    Label1.Text = row.Cells[1].Text;

    OleDbConnection myConnection = new OleDbConnection("Provider=Microsoft.Jet.OLEDB.4.0;Data Source=" + dbpath + "/secure_user/data/data.mdb");
    OleDbDataAdapter adapter = new OleDbDataAdapter("SELECT tasks.Task,tasks.Priority,tasks.Done,taska.Hours FROM projects,tasks WHERE tasks.Username='" + uname + "' AND tasks.Project='" + Label1.Text + "'", myConnection);
    DataTable table = new DataTable();
    adapter.Fill(table);
    adapter.Dispose();
    GridView2.DataSource = table;
    GridView2.DataBind();
    GridView2.Visible = true;
}

It displays with no error, but it does 5 times no matter what project I select from GridView1, it always displays GridView2 (second table) content 5 times in a row. What could be the problem?

Answer 1

Looks like you have something wrong in your query. Try using INNER JOIN instead of ,.

Instead of this:

SELECT tasks.Task, tasks.Priority, tasks.Done, tasks.Hours
FROM projects, tasks
WHERE tasks.Username='" + uname + "' AND tasks.Project='" + Label1.Text + "'

Try this:

SELECT tasks.Task, tasks.Priority, tasks.Done, tasks.Hours
FROM projects INNER JOIN tasks ON projects.ID = tasks.ProjectID --> may not be correct depends on your table structure
WHERE tasks.Username='" + uname + "' AND tasks.Project='" + Label1.Text + "'

Another thing: building a SQL query like that is prone to SQL Injection attack.